I've subscribed for Sonar Pro for ~20€ / month.
 
Please correct my following assumptions
1.) If I pay 20€ for 12 month I own Sonar Pro. At this point I can
  a: Cancel my subscription and receive no more updates after additional 12 month
  b: Pay on 10€ / month and receive all updates for as long as I pay, eventually keep the upgraded version if I cancel
  c: Upgrade my plan to Sonar Platinum and pay now ~30€ / month for 12 additional month. After that I own Sonar Platinum
 
2.) Once I own Platinum I will
  a: Receive lifetime upgrades of everything Platinum includes, all new Plugins, younameit..?  or..
  b: Have to pay on ~15€ / month to receive the full update pack?
 
Thanks for clarifying!
 
 

Everything up until "lifetime upgrades" is correct I think. That is/was a separate deal.

Well, technically nobody ever "owns" software. You just have a license to use it, and that applies to everything from Windows to Solitaire.
 
However, assumption #1 is correct in essence. SONAR will not stop working if you stop paying, which is why it's technically not a subscription, which implies a rental. Some software does take that approach, and it's an unpopular one. With SONAR you're paying for updates.
 
So yes, if you abandon the payment plan you'll still "own" the application forever, insofar as it will continue to work. But it'll be frozen at that revision. Exactly like it used to be when you bought, say, SONAR 6. You would not have been entitled to the new features and instruments in SONAR 7 without buying S7 (albeit at a discount). 
 
Cakewalk does [still? not sure] offer an attractive alternative, which is the for-life option. You pay one time up front and then get updates forever with no additional fees. 
 

bitflipper
Well, technically nobody ever "owns" software. You just have a license to use it, and that applies to everything from Windows to Solitaire.
 
However, assumption #1 is correct in essence. SONAR will not stop working if you stop paying, which is why it's technically not a subscription, which implies a rental. Some software does take that approach, and it's an unpopular one. With SONAR you're paying for updates.
 
So yes, if you abandon the payment plan you'll still "own" the application forever, insofar as it will continue to work. But it'll be frozen at that revision. Exactly like it used to be when you bought, say, SONAR 6. You would not have been entitled to the new features and instruments in SONAR 7 without buying S7 (albeit at a discount). 
 
Cakewalk does [still? not sure] offer an attractive alternative, which is the for-life option. You pay one time up front and then get updates forever with no additional fees. 
 

The lifetime update option expired at midnight last night

Yup, I saw Craig's post right after making my reply above. The for-life option was a one-time deal.

I bought the lifetime update yesterday. It is still on the website though. So, MAYBE, it can still be purchased - at least for today.

Just now I saw.... it says:

Big Bundles. Big Names. Huge Savings.

            Don't miss out: now through December 31, save big on popular bundles with iZotope, Softube, Overloud and XLN Audio to perfect your productions.            These artisinal collections have been specially hand-crafted by Cakewalk's little elves to help you get the most out of SONAR Platinum!
 

Don't have SONAR Platinum?

Now through December 31 you can update to SONAR Platinum with lifetime updates AND take advantage of these special offers
 
 
Logically now its Jan 2nd. So one has 363 days in hand.... [No year mentioned]
 
Just curious
 
Edit: added LTU as well.

Thanks guys.
 
But honestly I'm even more confused now. When I'm logged in and go to the Cakewalk Store, all prices have changed. E.g. Sonar Professional has it's original price crossed out and below it reads: "your price: ~100€"
 
Is there a sale going on for everyone or could I now purchase Sonar Pro for 100€ and cancel my subscription next month? I don't get it. I mean I could purchase stuff for thousands of bucks now at 50% off or more, just because I payed the 20€ subscription one single time??

You do have the option of purchasing SONAR every year and skipping the subscription. That's how we all did it for many years. Monetarily, you might even come out ahead. But in the interim you'd be missing out on all the incremental improvements. 

The whole subscription/pay ahead/lifetime deal is pretty confusing I have to admit.